Bower, J. E., Garet, D., Sternlieb, B., Ganz, P. A., Irwin, M. R., Olmstead, R., & Greendale, G. (2012). Yoga for persistent fatigue in breast cancer survivors: a randomized controlled trial. Cancer, 118, 3766–3775.

To examine, relative to a health education control, the feasibility and efficacy of an Iyengar yoga intervention for breast cancer survivors with persistent posttreatment fatigue.

Outcome assessors of the performance tasks were blinded to group assignment. The intervention was briefly but fully described, and then participants were randomly assigned to a group that received a 12-week, Iyengar-based yoga intervention or a group that received 12 weeks of a health education (control group).

• The sample was comprised of 31 women.
• Mean age was 54.4 years (standard deviation [SD] = 5.7 years) in the intervention group and 53.3 years (SD = 4 years) in the control group.
• All participants had stage 0 to II breast cancer.
• Most participants were white.
• The range of education was high school completion through graduate degree.
• Twenty-four participants were completing radiotherapy, 17 were completing chemotherapy, and 22 were receiving hormone therapy.
• In the intervention group, median time posttreatment was 1.7 years (range 0.7–4.1).
• Breast cancer survivors with posttreatment fatigue were recruited through multiple mechanisms. Inclusion and exclusion criteria were applied.
• The original enrollment target was 72 participants; researchers assumed a 20% loss to follow-up. Because of the stringent enrollment plan, the sample size was smaller than expected.
   

• Single site
• Outpatient
• University of California, Los Angeles
   

• Patients were undergoing the posttreatment phase of care.
• The study has clinical applicability for survivorship and late effects and survivorship.

The study was a randomized, controlled trial.

• Fatigue Symptom Inventory (FSI)
• Multidimensional Fatigue Symptom Inventory (MFSI), to assess vigor
• Beck Depression Inventory II (BDI-II)
• Pittsburgh Sleep Quality Index (PSQI)
• Perceived Stress Scale (PSS)
• Timed chair stands and functional reach test, to assess physical performance
• Medical Outcomes Study (MOS)
   

Relative to the control group, fatigue severity in the intervention group declined significantly (p = 0.032) from baseline to posttreatment and over the three-month follow-up. In addition, relative to the control group, the yoga group had significant (p = 0.011) increases in vigor. Both groups had positive changes in symptoms of depression and perceived stress (p < 0.05). The authors noted no significant changes in sleep or physical performance. 

One adverse protocol-related event occurred:  a participant with a history of back problems experienced a back spasm in yoga class. After evaluation by her physician, she returned to class.

A targeted yoga intervention led to a significant reduction in fatigue and improvement in vigor among breast cancer survivors with persistent fatigue symptoms. This conclusion should be understood in the context of the study:  participants were relatively healthy and without comorbid conditions found in the general population.

• The study had a small sample size, with less than 100 participants.
• Some participants had been living with cancer for more than five years, which was longer than most in the study had been living with cancer.
• Because of the context of the study, researchers were unable to use a double-blind design.
• The study included multiple conditions.
• The results were not generalizable.

This study offered minimal conclusive data in support of the intervention. Preliminary findings indicated that the yoga intervention is feasible and safe and has a positive effect on fatigue. A larger trial that includes participants with common comorbid conditions—a study more representative of the general population of women with breast cancer posttreatment—is warranted. Secondary outcomes included vigor, symptoms of depression, sleep, perceived stress, and physical performance.